The subject matter described herein relates generally to wind turbines and, more particularly, to a wind turbine and a method of controlling at least one wind turbine within a wind turbine farm.
Generally, a wind turbine includes a rotor that includes a rotatable hub assembly having multiple blades. The blades transform wind energy into a mechanical rotational torque that drives one or more generators via the rotor. The generators are sometimes, but not always, rotationally coupled to the rotor through a gearbox. The gearbox steps up the inherently low rotational speed of the rotor for the generator to efficiently convert the rotational mechanical energy to electrical energy, which is fed into a utility grid via at least one electrical connection. Gearless direct drive wind turbines also exist. The rotor, generator, gearbox and other components are typically mounted within a housing, or nacelle, that is positioned on a base that includes a truss or tubular tower. At least some of the known wind turbines are physically nested together in a common geographical region to form a wind turbine farm.
In at least some known wind turbines, combinations of local air conditions and wind turbine operational conditions cooperate to induce deflections of one or more of the rotating rotor blades. Some of such blade deflections may be sufficient to reduce a distance between the rotating blades and the truss or tubular tower, thereby increasing a probability of contact between the two. Such contact may increase operational maintenance and replacement costs, decrease electric power generation during associated maintenance outages, and decrease expected life spans of the blades and the truss or tower. In some of the known wind turbines, blade deflection sensors are installed on each of the blades to provide indications to operators of existing blade deflections. However, installation of blade deflection sensors increases capital costs of wind turbine construction and operational maintenance costs, including preventative maintenance and calibration activities.